22263 C.K.Vijayalakshmi et al./ Elixir Entomology 68 (2014) 22263-22266

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Elixir Entomology 68 (2014) 22263-22266

Xylosandrus Compactus (EICHH) (Coleoptera: ), the shot hole borer or black twig borer- a review C.K. Vijayalakshmi 1, K.Tintumol 1, Sabeeda 1 and P.K. Vinodkumar 2 1Regional Research Station, Wayanad, Kerala, India 673 123. 2Central Coffee Research Institute, Chikmagalur , Karnataka.

ARTICLE INFO ABSTRACT Article history: Shot hole borer, compactus (Eichh) is one of the most serious pests of robusta Received: 3 January 2014; coffee. Small black bore into green succulent stem and make galleries which leads Received in revised form: drying of the twig. Ambrosia fungus grows inside the gallery helps the development of the 22 February 2014; beetle. Whole stages develop inside the gallery and this concealed nature makes it difficult Accepted: 4 March 2014; to control. The present review discusses the distribution, , biology and the control of shot hole borer. Keywords © 2014 Elixir All rights reserved. Shot hole borer, Coffee, Robusta, Pest management.

Introduction Xylosandrus is distinguished by having the anterior coxae ( Eichh) commonly known as shot widely separated rather than contiguous or narrowly separated. hole borer or black twig borer or , comes under Bright (1986) and Wood (1982) recognised Xylosandrus as a the family Curculionidae of the order Coleoptera. The black distinct genus with about 25 worldwide. twig borer is a serious pest of coffee, Pierra Description (esp.var.robusta Ineae) (Brader, 1964). This beetle is highly Shot hole borer is a very small, shiny, black cylindrical problematic since it attacks healthy plants ( Dixon et al, beetle. Adult female length is 1.4 to 1.9 mm, width 0.7 to 0.8 2005).Twig borer belongs to the tribe in which all mm body stout, cylindrical, elongate, brown to black, distinct the members feed on ambrosia fungus and are called ambrosia punctures on pronotum posterior, transversely oriented hair tuft . solani is the fungus, associated with the at base of pronotum and long strial setae. ambrosia beetle Xylosandrus compactus (ISSG, 2005). Male of shot hole borers are rarely found and flightless. Distribution Body rounded, dark, reddish brown and all characters are poorly The black twig borer is native to Asia. It has spread to the developed. Eggs are extremely small, oval, white and coffee growing areas of the world. It is widely distributed in the translucent. Grubs are white and legless. Young grubs are coffee growing areas of East Africa, West Africa, Madagascar, pointed at the rear while older grubs have a brownish heads and Mauritius, Seychelles, India, Malaysia, Java, Sumatra, and Fiji. rounded tail. Pupa about the size of adult with distinct legs, In Hawaii the first occurrence was reported in 1961 and spread wings and head (Barker, 1994). to all islands of Hawaii (Hara et al 1976). Pantropical Hosts of Shot-hole borer distribution of the beetles includes Brazil, Cuba, Indonesia, There are 224 plant species belong to 62 families, are Japan and Sri Lanka (Ceylon) (Bright, 1968, Murayama & susceptible for black twig borer infestation (Ngoan et al 1976) Kalshoven 1962, Wood 1982). include coffee, cocao, , brush box,( Tristania conferta), Pathways to new locations turpentine tree ( Syncarpia glomulifers ), paper-bark( Melaleuca These beetles are breed under the bark therefore making it leucadendron ), red- iron bark eucalyptus ( Eucalyptus easy to transport them through International trade (ISSG 2005). sideroxylon), black butt eucalyptus ( E. pilularis ), robust Black twig borers/shot hole borers are commonly intercepted in eucalyptus( E.robusta ) Koa haole( Leuceana glauca ), guava, food products such as seeds and nuts. Black twig borers are vervain( Stachytarpheta jamaicensis) , Christmas berry(Schinus among the most commonly intercepted families of on terebinthifolia) floral red ginger, litvhi, macadamia, mango, solid wood packing materials. Scolytids were the most mahagony, kukui, star jasmine, pikake, periwinkle, Surinam commonly intercepted group of insects found in association with cherry, Hibiscus, Cattleya , Dendrobium, Epidendrum, Vanda solid wood packing material in Chile and Newzeland (Haack, and Anthurium( Davis,1963;Davis 1969;Dixon and woodruff, 2003). 1982; Hara and Beardsley, 1979; Mangold et al, 1977;Marsden, Taxonomy 1979; Nelson and Davis, 1972). It also attacks Clerodendron, Until 1962 the species was identified as Xylosandrus dadap, neem, Annata sp. and Crotalaria (Anonymous 2000). It morstatti Hagedorn when Murayama and Kalshoven recognised also attacks apple, pear, cherry (Mike et al , 1993). the precedence of Eichoff's 1875 description of Xyleborus Biology compactus . In 1963, Brown resurrected the genus Xylosandrus The life cycle of shot hole borer is completed in about a Reitter (1913) from its long time synonymy with Xyleborus. month. Males spend entire lives inside the brood gallery.

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Females lay eggs inside the gallery. Hatched females mate developed feeding strategies for handling the various types of inside the brood chamber and leave the gallery in search for new fungal substrates and specific morphological adaptations plants. Females without mating are able to reproduce and the (mainly mouth parts) to carry out these strategies (Lawrence, offspring are all males (Le Pelley, 1968). 1989).Initially the ambrosia was considered to be a mixture of Eggs are smooth, white, oval less than 1mm long and are spittle and crusts of coagulated sap, but subsequently it laid inside the galleries. They hatch in about 3-5 days (Hara and was found to be fungal in nature. Ambrosia fungi are not able to Beardsley, 1979). Females lay eggs 7-8 days after the entry exist without the beetles. They are transported and cultured for (Brader, 1964). Grubs are white and legless. Usually two larval food by the beetles (Beaver, 1989). The fungi invade phloem instars are found which nourishes on the ambrosia fungus and and wood, spread widely, forming ambrosial layers covering the pupates after 7 days (Hara and Beardsley, 1979). Some studies walls of the beetle gallery. These layers are browsed upon by the showed that, there were three instars as per the head larval and adult stages of the beetle (Tanada and Harry, 1993). measurements of the larvae. Pupae are initially white, later The ambrosia fungi are highly specialized forms and are not changes to light brown before emerging. It takes atleast 6 days easily isolated and cultured. Most of them are known only in the (Hara and Beardsley, 1979). Adult females turn shiny black in imperfect state ( Duteromycotina ) and where the perfect states 3- 4 days after emergence. Males turn from light brown to are known, they belong mainly to Ascomycotina and a few to reddish brown in 3 – 4 days (Hara and Beardsley, 1979). Basidiomycotina (Francke, 1967; Beaver 1989; Lawrence Damage 1989).The common genera of imperfect fungi are Fusarium, Beetles in the sub family Scolytinae are among the most Cephalosporium, and Ambrosiella and those of Ascomycetes are damaging insects in the world (ISSG, 2005). Xylosandrus Endomysopsis, Ascoidea, Ceratocystis. The ambrosia fungi are compactus (Eichhoff) is one of the few ambrosia beetles that pleomorphic and may form hyphae and an extended mycelium infest healthy plants. Shot-hole borer tunnels into woody twigs or produce ambrosia, or become yeast like in form (Tanada and leaving a pin-sized entry holes. Detection of the borer is difficult Harry, 1993). due to the cryptic lifestyle (Coyle, 2005). In coffee it attacks the The ambrosia fungi are not species specific to ambrosia tertiary branches. It causes serious problem for young coffee beetles, and other beetles may feed on them. The ambrosia plants since it attacks the main stem. The mining of the borer beetles and their larvae probably feed on a complex of fungi and can interfere with the movement of fluids through cambium bacteria (Haanstad and Morris 1985). between wood and bark (Mike et al, 1993) . A severe infestation The fungi are carried in specialized integumental organs can kill host plants, including large trees (Nelson and Davis, (Mycangia or Mycentangia) of the beetles (Baker and Morris, 1972; Hara and Sewake, 1990). Insects prefers internodal region 1968). The location of the organs is mainly in the head and for tunnelling (Anonymous, 2000). One or more females may thorax and rarely on the elytra and legs (Beaver, 1989). The occupy a twig or branch if the twig diameter is less than 7 mm, organs are generally found only in the female beetles. Some but up to 20 females can be found in branches of 8-22 mm beetles however, lack these organs and carry the fungi in their diameter. After entry they excavate galleries and lay eggs. digestive tracts or carry the spores in association with fatty or Beetles inoculate the host with an associated fungus and feed on oily secretions on their body surface. (Tanada and Harry, 1993). that fungus (Buss and Foltz, 2006). Damage is not caused by All the stages of the beetle feeds on the white, glistening feeding since beetle feeds on ambrosia fungus. Beetles ambrosia which provides complete nutrition for the growth and sometimes introduce pathogenic fungi or bacteria, which may reproduction of the beetle (Baker and Morris, 1968). cause wilting, die back or death. Excavation and introduction of The beetles carry the ambrosia fungus in specialised tubes, pathogens cause damage. Wilting of twigs becomes evident pouches, cavities or pits (Mycangia) that occur in different body within weeks after infestation. locations among the insect species. Depending upon the species Optimum conditions for the attack is a temperature of 26.5 0 the Mycangia may occur in the males only, the females only or C – 29 0 C and a relative humidity 72-78% in the absence of rain. in both sexes. (Batra, 1963). Adult females emerge in the large numbers in the afternoon (Le The mycangia are associated with thin-walled cells that Pelley, 1968). Flight capacity of the beetles has been reported secrete oily or waxy substance that protect the thin-walled upto vertical distance 7 mm, and 200 mm of longitudinal spores from desiccation. The mycangia are also associated with distance from plantations. The highest population occurs during various amino acids that are utilised for the germination of the the June- Sep. spores and the growth of the fungus. The gland cells are active Association with the fungus during the flight of the beetles, and the fungus actually grows Members of nearly all insect orders are associated with slowly as yeast-like cells that multiply by budding and fission. fungi (Hammond and Lawrence, 1989). In some cases specific Additionally, spores and cells of fungi other than the ambrosia fungi are cultivated under complex conditions. The insects fungi are selectively eliminated, perhaps due to special control the type, growth, and form of the fungi cultured in their chemicals secreted in the mycangia or by antibiotics produced gardens. In the absence of insects the fungal garden is soon over by the ambrosia fungi (Moore and Landecker, 1996). run by bacteria and other microorganisms and the cultured In Indian Muthappa and Venkatasubbaiah (1981) reported fungus is replaced by other fungi. The insects appear to maintain the presence of Ambrosia macrospore (fr. Grosmann) Batra in and cultivate their fungal gardens, through oral, anal and the tunnels of shot-hole borer on robusta coffee. Occurrence of epidermal excretions and through continuous harvest of the another species of Ambrosia fungus viz, Ambrosiella xylebori in fungal crop. The insect’s anatomy is modified for carrying and association with X. compactus on robusta coffee is also reported dispersing the fungus in order to ensure transmission from one (Bhat and Sreedharan, 1988). insect generation to the next (Tanada and Harry, 1993). Ambrosia fungi The ambrosia beetles are found mainly in the two families Ambrosia beetle line tunnels, chambers and galleries with a of Scolytidae and Platipodidae and also in Lamexylidae . They cushion like growth or ambrosia fungi. When originally differ from bark beetles in the feeding habit; they feed on fungi observed, the glistening layer of ambrosia fungi was thought to while the latter feed on wood and are serious pests. Beetles have be dried exuded sap(known then as “ambrosia”, the food or 22265 C.K.Vijayalakshmi et al./ Elixir Entomology 68 (2014) 22263-22266

drink of the gods).The ambrosia fungi are filamentous yeast- Injury of the wood by beetle facilitates rapid penetration by allies in the order Endomycetales (especially endomycopsis and the mycelium, and urea and uric acids in the beetle’s faeces Ascoidae) and Deuteromycota(especially Monilla and serve as an important source of nitrogen. Attempts to establish Ambrosiella ). The fungi form hyphae that penetrate through the the fungus in the host plant in the absence of the beetle have wood, while surface of the tunnels and galleries are covered been unsuccessful ( Moore and Landecker, 1996) with a palisade layer of conidiophores, conidia, and yeast -like Management of Xylosandrus sprout cells that bud from conidia. The yeast like cells Cultural control constitutes the ambrosial stage on which the beetles feed. It Prune the affected twigs two – three inches below the hole usually is the sole source of food for the larvae and is also and burn to destroy the beetle. It should be started as soon as the important in the diet of the adult. This symbiotic relationship first attack, and continued in regular intervals. Unwanted between the beetle and fungus is obligate, as neither the suckers should be removed and destroyed during summer, since ambrosia fungi nor the beetles are found without the other in the pest breed in the suckers during dry period(Anonymous, nature (Beaver, 1989; Kok, 1979; Norris, 1979). 2000). Practices that promote tree vigour and health will aid The wood within which the beetles and ambrosia fungi recovery from beetle damage (Dixon and Woodruff,1982; grow is not suitable as a sole source of food for the beetles. The Bambara, 2003). Maintaining adequate shade is also important wood consists mainly of cellulose and lignin, which are resistant for the management of borer. In Malaysia, Anaur(1986) found to digestion by enzymes found in most beetles. Compared with that SHB attack on robusta and Liberian coffee in shaded and other organic resources, the wood is a poor source of nitrogen open conditions are highly different; the frequency and severity and is also deficient in B vitamins and sterols, which are of damage was higher in shade grown robusta. required by the beetles. As the mycelium of the fungi grows Biological control through the wood outside of the tunnels, its enzyme degrades the Shot hole borers are preyed upon by woodpeckers, cellulose and lignin, and nutrients are translocated through the checkered beetles, parasitic hymeopterans and parasitic bacteria hyphae to promote growth of the fungal cells lining the tunnels and fungi (Mike et al , 1993). and galleries. The growth habit of the ambrosia fungi provides Parasites: The ectoparasitic mites Pyemotes harsfsi , feed on great advantage to the beetles because nutrients become the immature stages of the borer, and during hot months on fresh available to them with a minimum of effort expended to produce emerged adults( Balakrishnan et al ., 1994 b). Another species tunnels. P. ventricosus parasitizing the borer was reported from Ivory The ambrosia fungi provide the beetles with a food rich in Cost (Lavabre, 1962). A Bethilid ( undescribed) is reported proteins, B-vitamins, and sterols such as ergosterol. The sterols asparasitizing the pest (Le Pelley, 1968). A Eulophid , are essential for the normal sexual development of the beetles, Tetrastichus sp. Nr. Xylebororum attack borer which was first as they are required for egg-hatching, complete larval time reported from India during 1992(Dhanam et al, 1992). development, pupation and oocyte development. There is Solitary pupae of Eurytoma sp. ( Hymenoptera: Eurytomidae) evidence that atleast some of the ambrosia beetles may have an were also found to be attacking this insect(Balakrishnan et al , absolute requirement for the ergosterol produced by the fungi. 1994 b). When the beetles bore new tunnels in the spring, they Predators: The grub of a clerid beetle Callimerus sp. prey on prepare a mixture of faeces and wood fragments, which they the pest . Eupelmus sp. is reported as predator which feeds on smear on the tunnel walls as a bed for the fungi growth. The egg, larvae and pupae of the beetle( Balakrishnan et al , 1989). beds are inoculated with ambrosia fungi through incidental Life stages of X. compatcus are preyed by Formicidae contact with the mycangia. The adult insects must feed on the (Balakrishnan et al., 1994 b). ambrosia fungus in order to reproduce sexually-they are Competitors: Asynapta, coming under the family dependent upon particular amino acids present in the ambrosia Cecidomyiidae is reported as the competitor of the borer fungus. If the founding beetles are unable to culture the (Balakrishnan et al, 1994 b). ambrosia fungi, they eventually die without laying eggs. Entomopathogenic fungus: Beauveria bassiana attacks X. Assuming that the ambrosia fungi are established and the adult compactus. Natural infection of this fungus was very low, but an beetles do reproduce, they must continue to tend the ambrosial experiment with sprays of conidial suspensions of the fungus at fungus until the larvae reach adulthood. The beetles tend to 10 7 / ml water caused 21 % of the colonies to be infested after maintain a pure culture of the ambrosia fungus and are able to two weeks (Balakrishnan et al ., 1994). Paecilomyces do so when the tunnels are fresh(Moore and Landecker, 1996). fumoroseus and Verticillium lecanii are other two fungi found Often, secondary ambrosia fungi (Dipodascopsis) may in India attacking X. compactus (Balakrishnan et al, 1994 b). appear in the tunnel and the beetles may feed on them. Unlike Chemical control the primary ambrosia fungus, these secondary fungi are not Due to the mode of attack it is not economically feasible to transported in mycangia, and the beetle is not dependent on their control the pest in Coffee. Complete and continuous protection presence. The ambrosial stage is dominant as long as the beetles of the plant is difficult (Anonymous,2000). Meiffern and Belin are present, but the beetles vacate the tunnel, the mycelial form (1961) claimed considerable success when insecticides are dominates (as it does in pure culture). Also, contaminating fungi sprayed mixed with fungicides. Chlorpyrifos provided 83% of several types develop profusely in a vacated tunnel. mortality for all the stages of this pest in flowering dogwood in The beetles obviously benefit greatly from this symbiotic Florida (Mangold et al., 1977). Chlorpyrifos shows 100% relationship, obtaining nitrogen compounds, vitamins, and mortality of adult females (Hata et al , 1989). A systemic sterols from the fungus required for their growth and fungicide, Propiconazole which prevents the fungal spores from reproduction. The fungus also gains from this symbiotic germinating was found effective to control the borer. association in several ways. Because the fungus is protected Yan et al (2001) used quinalphos or chlorpyrifos plus from desiccation during transport in the mycangia, the number cymethrin mixed with yellow soil and painted on the main stem of cells available for inoculation of wood is increased by the of chest nut tree and reported good control. mycangial secretions. 22266 C.K.Vijayalakshmi et al./ Elixir Entomology 68 (2014) 22263-22266

Green Japanese beetle traps baited with ethanol were the Hara AH , Beardsely JW Jr. The biology of the black twig most effective traps for X. compatcus was significantly more borer, Xylosandruc compactus (Eichhoff), in Hawaii. Pro. effective than multiple funnel traps baited with ethanol( Elsie et Hawaiian Entomol Soc. 1979 18(1): 55-70. al., 2006). Invasive Species Specialist Group (ISSG). Global Invasive References Species Database. Xylosandrus compactus (Eichhoff, 1875) Anonymous. Coffee guide. Central Coffee Research Institute, 2005. Chikmagalur, India; 2000. p. 85-87. Lavabre EM. Le Scolyte des branchettes du cafeier robusta Balakrishnan MM, Sreedharan K, Bhat PK. New natural Xyleborus morstatti Haged, Nogent-sur-Marne. Cafe Cacao The. enemies of Xylosandrus compactus. Journal of Coffee Research. 1958 3(1) :21-33. 1994 24(1): 33-35. Lavabre EMRecherches biologiques et ecologiques sur le Brader L. Etude de la relation entre le Scolyte des rameaux du scolyte des rameaux de coffiers. Institute Francais du Cafe et de cafeier Xyleborus compactus Eichh. Et sa plante-hote, Cacao, Bull. 1962 No. 2:137. Meded.Landb Hoogesch.,Wageningen . 1964 64(7) : 109. Le Pelley RH Pest of Coffee, tropical Science series, Longmans Bright Jr DE. Review of the tribe Xyleborini in America north Publications; 1968. p.16-146. of Mexico (Coleoptera : Scolytidae).Canadian Entomologist. Mangold JR, Wilkinson RC, Short DE, Chlorpyrifos sprays for 1968 100 : 1288-1323. control of Xylosandrus compactus in flowering dogwood. Buss EA, Foltz JL. Insect borers of trees and shrubs. University J.Econ.Ent.Soc. 1977 70:789-790. of Florida, IFAS; 2006. Murayama JJ, Kalshoven GE, Xyleborus morstatti. Hag. A Coyle DR, Booth DC, Wallace MS. Ambrosia beetle synonym of X. compactus Eichh. Ent. Ber.Amst. 1962 22:247- (Coleoptera: Scolytidae) species, flight, and attack on living 250 . eastern cottonwood trees. Journal of Economic Entomology . Mike, Phil Vanbuskrik Orchad Pest Management. Tree fruit and 2005 98:2049-2057. research extension center.1993. Dhanam M, Raju T, Bhat PK. Tetrastichus sp. nr. Xylebororum Nelson RE, Davis CJ. Black twig borer, a tree killer in Hawaii, Domenichini (Hymenoptera: Eulophidae), A natural enemy of U.S. Dept of Agri., Berkely, CA, UDA Forest Service Research Xylosandrus compactus (Eichhoff). Journal of Coffee Research. Note PSW;1972 :274. 1992 22(7):127-128. Ngoan ND, Wikinson RC, Short DE, Moses CS, Mangold Dixon W N, Woodruff RE, Foltz JL.Black twig borer, JR.Biology of an introduced ambrosia beetle, Xylosandrus Xylosandrus compactus (Eichhoff). Featured Creatures. compactus, in Florida, Annals of the Entomological society of University of Florida; 2005 America. 1976 69:872-876. Elsie B, Mark GW, Virginia ES, Nancy G. Effect of three Wood SL. The bark and ambrosia beetles of North and Centra; formulations of a chemical repellent, verbenone, on X. America (Coleoptera:Scolytidae), a taxonomic monograph. compactus (Coleoptera: Curculionidae) in Coffee and Flueggea Great Basin Naturalist No. 6 Brigham Young Univresity; 1982. plants. Annual meeting of Entomological Society of America; p.1359 2006. Hara AH, Beardsely JW Jr. The biology of the black twig borer, Xylosandrus compactus (Eichoff) in Hawaii. Proceedings of the Hawaiian Entomological Society; 1976 23(1):55-70.